/Engine/Source/Editor/Kismet/Classes/BlueprintPaletteFavorites.h
Sometime favorites can be coming from user edited .ini files, so this converts that readable text into a favorite (since the strings are user generated, there could be some error, so sure to check its validity).
FFavoritedBlueprintPaletteItem ( [FString](API\Runtime\Core\Containers\FString) const & SerializedAction )